Reliability and stability of executive functioning in older adults.

A number of methodological questions have been raised about the reliability and validity of measuring executive functioning (EF) across multiple time points. In this study, correlational and latent-variable analyses were used to examine test-retest reliability of 5 common measures of EF and the stability of a latent EF construct. One hundred eighteen nondemented older adults were tested twice over a 4- to 8-week period. Findings demonstrated modest reliability of individual EF measures but very high stability of a latent EF construct. Relative contributions of each measure to the latent EF factor did not change across measurement trials. In addition, age-related effects on EF were similar at the 2 time points and were within the expected range. Implications for future studies of EF are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Clinical trial of a new lightwand device (Trachlight) to intubate the trachea

BACKGROUND: Transillumination of the soft tissue of the neck using a lighted stylet (lightwand) is an effective and safe intubating technique. A newly designed lightwand (Trachlight) incorporates modifications to improve the brightness of the light source as well as flexibility. The goal of this study was to determine the effectiveness and safety of this device in intubating the trachea of elective surgical patients. METHODS: Healthy surgical patients were studied. Patients with known or potential problems with intubation were excluded. During general anesthesia, the tracheas were intubated randomly using either the Trachlight or the laryngoscope. Failure to intubate was defined as lack of successful intubation after three attempts. The duration of each attempt was recorded as the time from insertion of the device into the oropharynx to the time of its removal. The total time to intubation (TTI), an overall measure of the ease of intubation, was defined as the sum of the durations of all (as many as three) intubation attempts. Complications, such as mucosal bleeding, lacerations, dental injury, and sore throat, were recorded. RESULTS: Nine hundred fifty patients (479 in the Trachlight group and 471 in the laryngoscope group) were studied. There was a 1% failure rate with the Trachlight, and 92% of intubations were successful on the first attempt, compared with a 3% failure rate and an 89% success rate on the first attempt with the laryngoscope (P not significant). All failures were followed by successful intubation using the alternate device. The TTI was significantly less with the Trachlight compared with the laryngoscope (15.7 +/- 10.8 vs. 19.6 +/- 23.7 s). For laryngoscopic intubation, the TTI was longer for patients with limited mandibular protrusion and mentohyoid distance, with a larger circumference of the neck, and with a high classification according to Mallampatti et al. However, there was no relation between the TTI and any of the airway parameters for Trachlight. There were significantly fewer traumatic events in the Trachlight group than in the laryngoscope group (10 vs. 37). More patients complained of sore throat in the laryngoscope group than in the Trachlight group (25.3% vs. 17.1%). CONCLUSIONS: In contrast to laryngoscopy, the ease of intubation using the Trachlight does not appear to be influenced by anatomic variations of the upper airway. Intubation occasionally failed with the Trachlight but in all cases was resolved with direct laryngoscopy. The failures of direct laryngoscopy were resolved with Trachlight. Thus the combined technique was 100% successful in intubating the tracheas of all patients.     

Role of Specimen Geometry in the Effect of Fiber Orientation on the Thermal Conductivity of a Uniaxial Carbon-Fiber-Reinforced Aluminoborosilicate Glass-Matrix Composite

A study concerning the effect of fiber orientation on the thermal conductivity of a uniaxial carbon-fiber-reinforced borosilicate glass was conducted. For thin specimens, and thick specimens with specimen sides cut parallel to the fiber direction, the dependence of thermal conductivity on fiber orientation showed excellent agreement with theoretical behavior predicted for a composite infinite in extent. In contrast, the thermal conductivity data for rectangular thick specimens fell well below the data for the thin and angled specimens. For fiber orientation of 45° and higher, at which the heat was directed toward the side of the specimen rather than across, the thermal conductivity values showed excellent agreement with theoretical behavior predicted for a finite composite strip with insulated sides.     

On a bounded solution to a pair of coupled nonlinear ordinary differential equations

We present a bounded, decaying solution to a pair of coupled, nonlinear second-order ordinary differential equations arising in the theory of natural convection. The solution is found by transforming the problem into a non-autonomous system in the phase-plane. A uniqueness proof is given for the bounded solution.     

Targets and methods for the detection of processed animal proteins in animal feedstuffs

Bovine spongiform encephalopathy (BSE), or ‘mad cow disease’, is one of several transmissable spongiform encephalopathies (TSEs) known to affect certain mammals and is spread through the ingestion of infected animal tissue. It is believed that the inadvertent contamination of meat and bone meal (MBM) with infected animal tissue and the subsequent use of this material as a feed supplement contributed to the spread of the disease in cattle. As a result, the use of processed animal proteins (PAPs) in animal feeds is regulated in many parts of the world. Although feed testing is the only definitive means to certify compliance, regulatory compliance often relies solely on paper certification. Recently, rapid methods have become available that can be used by regulators to determine compliance during routine inspections. We describe a rapid, immunochromatographic strip test that can detect 0.1% MBM in animal feed. The test takes 15 min to perform and large numbers of samples can be screened for PAPs simultaneously.     

Peridynamic modeling of concrete structures

The peridynamic model described in Silling (Silling, S.A., 1998. Reformation of Elasticity Theory for Discontinuous and Long-Range Forces, SAND98-2176. Sandia National Laboratories, Albuquerque, NM), being a central-force model, is limited to modeling materials with a Poisson's ratio of 1/4. In this paper, the peridynamic model is generalized by adding pairwise peridynamic moments to simulate linear elastic materials with varying Poisson's ratios. The new model is called the “micropolar peridynamic model”. The micropolar peridynamic model is placed within a finite element context to enable efficacious application of boundary conditions and efficient computational solutions using an implicit, rather than an explicit solution algorithm. The implicit solution algorithm is suitable for quasistatic simulation of damage and cracking in concrete structures. With this new model, very simple tensile damage mechanisms at the micro structural (peridynamic) level are sufficient to explain a great deal of the microcracking (damage) and fracture mechanics observed in concrete structures. The new implementation appears to be computationally efficient.     

Non-invasive headspace measurement for characterizing oxygen-scavenging in polymers

A non-invasive headspace analysis method to measure rate and amount of oxygen uptake in oxygen-scavenging polymers is presented. Oxygen uptake data for metal-catalyzed poly(1,4-butadiene) at 30 °C are provided to illustrate the method. These data were obtained by measuring oxygen headspace concentration above the scavenging polymer with an OxySense^® 200T non-invasive oxygen sensor, and, for comparison, oxygen uptake was measured with an analytical balance. Excellent agreement was observed between these two independent experiments.     

Obituaries: Elizabeth Douvan (1926-2002).

Presents an obituary for Elizabeth Douvan (1926-2002). Douvan was a pioneer in the study of changing gender, work, and family roles; personal values; and well-being in the second half of the 20th century. Through her research, she contributed to the interdisciplinary fields of social psychology and women's studies while building and strengthening institutions that remain committed to the same mission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Aspects of social and emotional competence in adult attention-deficit/hyperactivity disorder.

Social and emotional competence were evaluated using self-report and behavioral measures in adults with attention-deficit/hyperactivity disorder (ADHD) and controls. Adults with ADHD viewed themselves as less socially competent but more sensitive toward violations of social norms than controls. Films depicting emotional interactions were used to assess linguistic properties of free recall and perceived emotional intensity. Although adults with ADHD used more words to describe the scenes, they used fewer emotion-related words, despite rating the emotions depicted as more intense than did controls. In contrast, no group differences for words depicting social or cognitive processes were observed. Overall, adults with ADHD appear more aware of their problems in social versus emotional skills. Findings may have implications for improving the psychosocial functioning of these adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypnosis and clinical pain.

Hypnosis has been demonstrated to reduce analogue pain, and studies on the mechanisms of laboratory pain reduction have provided useful applications to clinical populations. Studies showing central nervous system activity during hypnotic procedures offer preliminary information concerning possible physiological mechanisms of hypnotic analgesia. Randomized controlled studies with clinical populations indicate that hypnosis has a reliable and significant impact on acute procedural pain and chronic pain conditions, Methodological issues of this body of research are discussed, as are methods to better integrate hypnosis into comprehensive pain treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)